Composites of metal carbide particles deposited on graphitized carbon flakes or particles may be used as supporting particulate structures for small particles of platinum or other metals displaying catalytic activity. The composite support particles are electrically conductive and, in many instances, such supported materials are useful as electrocatalysts in fuel cell electrodes, and for other energy conversion devices.
Traditional methods for preparing metal carbides, such as the carbides of molybdenum, tungsten, or vanadium, as particles on graphitized carbon composites are inefficient and often produce oversized particles. Graphitized carbon is prepared first, and then suitable precursors of Mo, W, and/or V are deposited onto the graphitized carbon. The metal precursor and carbon mixture is then heated to high temperatures to form composites of the metal carbides on graphitized carbon. The preparation method is complex and not very effective. For example, the dispersion of the carbide particles on graphitized carbon is uneven, and the sizes of the particles size are usually larger than 50 nm. The resulting size of the metal carbide in the composite is often found to reduce any cooperative catalytic effect between later deposited catalyst particles (such as precious metal particles) and the larger metal carbides.
There remains a need for a faster and better process to provide more effective forms of metal carbides on graphitized carbon.